Lizard myogenic cells from the regenerating tail of Anolis carolinensis are readily cloned and cell lines can be routinely established. Such lines can be maintained indefinitely by subculturing every two weeks and will not fuse in a growth medium based on Ham's F10 unless it is supplemented with calcium. Prior to reaching the fusion stage they withdraw from the mitotic cycle and are at this time recognizable due to their spherical morphology. Current research involves studies of cAMP levels and myosin synthesis during the culture cycle and studies of the effects of various sera, antibiotics and nucleotide analogs on the cycle. Further studies are underway to test the potency of in vitro grown myogenic cells when these are returned to an in vivo regenerating environment. BIBLIOGRAPHIC REFERENCES: Cade, J. M. and P. G. Cox (1976). Hybrid myotube formation by the fusion of lizard and mouse myoblasts in vitro. J. Miss. Acad. Sci. 21:73. Fortenberry, J. H. and P. G. Cox (1976). The effects of theophylline on differentiating lizard myogenic cells in vitro. J. Miss. Acad. Sci. 21:74.